Drying means



C. H. CURRIER.

DRYING MEANS.

APPLICATION FILED FEB. 2, 1920.

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Patented Nov. M, 1922.

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A TOHNEY C. H. CURRIER.

DRYING MEANS.

APPLICATION FILED FEB. 2, 1920.

Patented Nov. M, 1922.

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maaier cams H. CUBRIER, or CHICAGO; ILLINOIS, Aiss'IGNoR To DarmeSYSTEMS, me.,

OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS DRYING MEANS.

application med February 2, 1920. serial No. 355,673.

To all 'wlwmz'tmay concern: e Be itv known that I, CHARLES H. CURBI'ER,a citizen of the United States of America, and a resident of Chica-go,county of Cook, and State of Illinois, have invented certain new anduseful Improvements in Drying Means, of which the following is aspecification. Y This invention relates to methods and i@ means adaptedyfor use Vin drying siccative coatings, as for instance, in drying-roominstallations for finishing automobile bodies, furniture, cabinets, andthe like, for which purpose itais desirable to treat the air to be usedrespecting' its temperature, humidity,

and purity.

Heretofore, attempering or conditioning devices have been installed forwashing, hu*- midifying and adjusting the temperature of 2e the air indrying rooms for paint,fx varnish,

and the like, for instance as set forth in my Patent No. 1,230,282,dated June 19, 1917, and separate drying rooms have been Sprovidedhaving dii'erent atmospheric conditions corresponding With'the severalstages generally recognized in the'drying process, namely the solventevaporatingv stage, the oil oxidizing stage, and the hard drying stage.

The main objects of this invention are to '30 provide an improvedprocess and corresponding means for drying siccative' coat- Lings,particularly finishing coatsv of varnish; to provide Successive stagesin a continuous drying process whereby the object to be treated may beadvanced from one stage to another, in which the atmospheric conditionsrespecting temperature and relativehumidity correspond with the degreeof dryness and hardness of the coating; to provide such do a Systemadapted for operation and use all in one room and includin a. commonattempering unit; to provide or improved distribution of the airincluding cross circulation,'and to provide for a final coolingtreateo'ment with correspondingly attempered air beforend-ischarge fromthe dryingroomnto provide in a pluristage dryingroom means- .of improvedform for circulating the air and distributing same etliectually toaccom- 5@ plish the ^purpose stated; to`provide distributedstep-by-'step attempering means adapted to efect the desired result; topro- -vide for advancing a number of lines of units to be driedfdirectlyfrom `the point of applying the coatings into and through the dryingroom in parallel relation to and independent of one another; and toprovide automatic means for maintaining the desired conditions at tapredetermined graded standard throughou 4 4An illustrative embodiment ofthis invention is shown in the accompanying drawings, in which Fig. l isa plan of an installation including the essential features of theinvention, the view being on a horizontal section at 1-1 of F1g. 2, andthe roof of the drying room being removed. l

-F ig. 2 is a vertical section 1 and 3, with the front end of the dryingroom removed.

Fig. 3 is an enlarged vertical section at wall and doors ,3`3 Von Fig.l.

sive. fluid pressure motor or diaphragm vallve system for automaticattempering contro In the construction shown in the drawings thepluristage drying room l is built into a larger building or workroom 2with provii sion`v adjacent to the ends of the drying room at 2 2onFigs.

for installation of the attempering apparatuses 3, such as illustratedat the right end A of Fig. 1.

The device 3 here shown includes air wash ing, heating and humidifyingmeans, namely,

the preheater 4, thev air s raying Washer and humidifier 5, andthe reeater 6. Adjacent thereto' are -ow-pans 7, drip-pans 8, and' means fordistributing the objects to be coated for parallel entry into thedrying, room,'namely,. a transverse runway or dis! tributing space 9.

The drying room as a Whole is'relatively long and narrow with a numberof parallel runways or tracks '10 extending lengthwise thereof for'simultaneous transmission of several lines of the coated objects 11through the drying room. As here shown there are ten ways which may beregarded as constituting groups A and B of five ways each for the twopans 7 respectively.

A pair of air conduits 12 ,and 13 extend lengthwise of the drying room,except adja-` Y for discharge to a greater or less extent into the openair, as provided forl at ventilator 14 at the outlet end of thecollecting main 13.

The conduit 12 which supplies the treated air for the main bodyfof thedrying room is disposed in the upper part of the workroom 2, preferablyover the center of the drying room and close to the roof 1 thereof. Itcomprises a plurality of sections or stages, for example 15, 16, and-17,corresponding -with the several progressive temperatures desired, withauxiliary heating means or boosters 18 at the junction points wheresuccessive stages meet. These temperature boosters 18. include steamcoils or the like, substantially as used in the heaters 4 and 6, as willbe understood, though not shown in detail. The relative humidity isdecreased by said boosters as the temperature is raised. Each state isprovided with a set of branch discharge conduits. 19 extending crosswiseof the room in opposite directions, and each having one or more arms 19extending downward through ceiling 1 and adjacent to the floor, whereupwardly turned discharge nozzles 20 are provided adapted to direct thetreated air diagonally upwardly and backward crosswise' against thecoated ob jects 11, and toward the return conduit 13. Said supplyconduit isdiminished in size as at the points21 between successivebranching points, so as to compensate for the dimlnishing air loadan'thus assure and maintain a uniform pressure for the discharge nozzles20 throughout the length of the con-V duit. The branches 19 are all ofsubstantially the same size and character, except that the brancheshaving more than one downward arm are somewhat larger than the others,and are reduced at the arm, branching points, as at 19". Part of thearms 19 are largely hidden behind the pillars 2 Which support the roof2".

Heatfis so a plied to the attempered air that a. relative y slight risein temperature is provided for the first stage; a somewhat highertemperature is provided for the second stage; and so on, except that inthe last stage the temperature is much lower, being preferably about thesame as in the first and is preferably near one side of the drying room.`It is provided with a series of branches or arms 22'extending throughsaid ceiling and downward adjacent to the floor where the ports 23 areprovided for collecting the.cooled and vitiated aifr in the lower partof the room. Said return conduit is somewhat similar to the supplyconduit respecting its adaptability to maintain a substantially uniformair pressure, sub-normal for suction, throughout its length. Thepressure is negativerather than positive, as the return conduit issubject to the suction of the blower, tending to cause a vacuumwherebythe air is driven into the conduit. For this purpose the size ofthe conduit is increased between the successive branching points 24 inthe direction extending toward the airtreating means 3.

The ventilator 14 in conduit 13 near the attemperer 3 is provided with avent ue 25 and an intake flue 26, said iiues, together with the mainflue at this point, being provided with valves or dampers 27, 28, and 29respectively, adapted to cause discharge of the collected air outside ofthe building and replacement thereof by fresh air, or the air may be allreturned .to the air-treating means, or if desired, the said valves maybe adjusted intermediately in such manner as to provide for artialexchange and partial re-treatment ofp the air, as will be readilyunderstood by reference to the drawirgs.

In this connection, see also my Patent 1,230,282. These valves may bethermostatically controlled as are the three similar valves shown inFig. 4 and hereinafter described.

The' distributing nozzles 20 are provided' with dampers 30 adapted foradjustment -for any desired capacityf Similarly, the collectingports 23are provided with adjustable dampers 30'. .A

In order to properly, completethe drying process so as to insure a hardand durable flawless finish, means are provided in the Ifinishingsection or final stage for applying relatively cool moist air to thegoods 11. For this purpose supply and return means 31' and 32 arefurnished which are independent of the similar air-carrying means abovedescribed. To this end the supply conduit 31, which may be placed underthe Hoor. is provided with two branches 33 and 34 disclosed crosswise ofthe drying room in spaced relation lengthwise of the room. Each of thesebranches diminish s in size step by step as at 35 between the outletnozzles 36, toward the extremities remote from the source. The returnconduit 32 is in the vupper part of the dryingroom and is disposedtransversely of the room: It is provided with a series of intake means37. This ner as described in connection with the corresponding apparatusat theo opposite end of the room. The attempering meansjor this Ysupplemental or finishingl step may to advantage be more or lesscombined with the main attemperer (Fig. 7 as will be understood,thoughab'ove' explained as a separate means.

Automatic control of the temperature of the air at the several .pointsindicated is effected by means of adjustable thermostats operativelyconnected to the heating means through the medium of fluid' pressuremotors. 4

.Such atmospherieally respnsive control means are shown in thefragmentary diagram of Fig. 8. The thermostatically controlled airpressure motors 45, 46, 47, 48, and

49, having valves connected therewith as uiiderstood in the art,regulatethe passage of steam from the supply main--50 to the pre- .f

heater 4f reheater 6, and the three boosters 18 respectively. The motor51 is hygrometrically responsive to the degree of humidity of the airleaving the reheater 6 and serves to supply humidifying .steam theretoifArequired in order to obtain the desired moisture.

vThe compressed -aiir for operating the motors 45 et cetera, is suppliedthrough the air main 52 leading to the air tank 53 adjacent tothecontrol operators panel 54.

The art of automatic control of the atrn'osphere by means which areresponsive to changes in temperature or humidity or both is already wellunderstood and full explained in the published art. Hence, will merelyrefer to certain United States patents showing atmosphericallyresponsive means` directly operate the steam valve, substantially as maybe used in my drying room equipment. The Johnson P atent No. 542,733shows a heat regulating apparatus, also using` air motors to operatesteam valves. he drying roomproper is preferably arranged, for thesake'of efliciency and economy, with its ceiling l little more than highenough to clear the objects 11 to be treated, and it is for this reasonthat the distributing and Ventilating conduits are,

disposed in the space above the drying-room roof. i

Referring to the air-treating equipment, it is to `be understood thatsame may beV of any of the various well-known forms adapted to effectthe desired treatment. The preheating member. the combined air-washerand humidifier, the reheating member, and the fan 55 and the motor 56for operating same may be variously designed to fit specific needs.

The return flue amd ventilator valves'42, 43, and 44, see Fig.`4, may toadvantage be operatively connected mechanically to one another andto athermostat 57, responsive to temperature changes "in said flue, wherebycontrol of the gradual replacement of used air by cool outside air maybe effected automatically in a manner to maintain any desiredtemperature at the point where the thermostat is located. The valvesl27, 28, and 29 at ventilator 14 may be controlled in similar manner. Y

The operation of the drying room and associated apparatus is as follows:The goods to be treated, for instance, automobile bodies, having beensprayed or otherwise ycoatedwith varnish at theflow pans, and havingstood sufiiciently over the drip pans to eliminate all surplus varnish,are moved forward from-the drip pans and distributed'transversely in thecross space at the front end of the dryer room and distributed ,to theseveral runways or lines 10. The goods are carried preferably about 28"from the floor, either on trucks or other suitable conveyers, not shown,as will be understood. The goods are permitted to rel main a s'ufiicientlength of time inthe firststage to partly dry the varnish, whereuponthey are moved forward successively 'through the remaining stages. AThismovement may be either slow andcontinuous or the goods may bee advancedin batches priodically.

In the next to the-laststage, the varnish drying is completed, whereuponthe goods are delivered tothe final or cooling stage', where the varnishis subjected to relatively cool -moist air, whereby it`is acclimated forsubsequent exposure to the outer air, without danger of developingfinecracks whichresult from sudden changes of temperature, and whereby it ismade ready to' be immediv jured by contact with workmens hands.

ately handled without danger of being inllore specifically, in the firststage, Where the temperature is moderate, the solvents and thinners areevaporated from the varnish and the work as a whole is heated up Withoutcausing any case hardening or the formation of a surface film. Thetemperature in this stage may be held at about 100 F. dry ,bulb and 86owet bulb. corresponding to a relative humidity of 56% and with amoisture content of 11.07 grains per cubic foot. In the second stage theoils in the varnish are oxidized, so as to put the varnish in asufficiently dry state to remove all trace of tackiness and to get theentire coat uniformly dry. This stage may be held at about 108O dry bulband 88o wet bulb, corresponding to a relative humidity of 45% and amoisture content of 11.12 grains per cubic foot.

In the third stage the varnish is sufliciently dried down and hardenedso that the object may be handled safely when cooled. ,Here the dry bulbmay be maintained at 120o and the wet bulb at 90, which corresponds to arelative humidity of 31% and moisture content of 10.73 grains per cubicfoot.

In the last. stage, which in this instance is the fourth, the coating issubjected to an appropriately conditioned cooling atmos-l phere, wherethe varnish is acclimated for exposure to the outer air. Here thetemperature may be 80o F. and therelative humidity 90%.

The operation of the air attempering and distributing apparatus issubstantially automatic when once adjusted and set into operation. Theair of the drying room is circulated through the attempering means 3 anddistributed in .the manner above described, the rate of flow and thegradual renewal of the air through the ventilators being controlled byatmospherically responsive means/adjusted manually from time to time tomaintain the precise conditions desired. The automatic temperaturecontrol means 4, 6, and .18, as well as the moisture controlling means,may also be adjusted from time to time as may be required.

In ordei` to insure a substantially uniform condition of the airadjacent to the ends and to enhance the efficiency of the device,movable closure means 58 and 59 are provided at the entrance anddischarge ends of the drying room. Said means may be providedl invarious ways, as for instance swinging doors or curtains may be used,las understood in theart.

' As a result of this unified pluristage proccess, the productis'uniform and dependable to a degree not practicable to obtaincommercially with devices heretofore known, and the efficiency of theplant and labor elements of production are greatly increased.

Although but two specific embodiments of this invention are herein shownand described, it is to be understood that'some of the details of themethods and .devices set forth may be altered or omitted withoutdeparting from the` spirit of this invention as defined by the followingclaims.

I claim:

1. A system of the character described, comprising a common drying room`adapted for the progressive movement therethrough of objects to bedried, means adapted to distribute a supply of air and to locallycirculate same in successive parts of said room, and a pluralityof airattempering means adapted and arranged in progressive order to effectnearly uniformgraduated adjustment of atmospheric `conditions along thepath of said objects, so as to closely approach the best dryingconditions for successive stages of the drying process.

2. A pluristage drying room provided with an air distributing mainextending therethrough, having attempering boosters positioned along itslength and air outlets between said boosters.

3. A pluristage drying room provided' with an air distributing mainhaving at-r tempering boosters positioned along its length,atmospherically responsive means operatively associated with each ofsaid boosters to automatically control their several effects inaccordance with predetermined atmospheric conditions for thecorresponding stages, and air outlets between said boosters. i

.4. A pluristage drying room having means to provide atmosphericconditions of upwardly progressive temperature in the first stages and adiminution of temperature in the final stage.4

5. A pluristage drying room having means to provide atmosphericconditions of upwardly progressive temperature in the first sta es and adiminution of temperature in t e final stage, means being providedadapted and arranged to preheat the air supply, means to wash the heatedair, and means for heating different parts of the air going to theinitial stages and-the finishing stage respectively to different degreesre' in the return main adapted to permit of partial renewal of the airto a greater or less extent during the operation of the device.

'7. A drying room having successive stages merging one into another inwhich the atmospheric conditions are serially adapted to effectsubstantially the following results respectively on siccative coatings,first, drying out of the solvmts and thinners, second. oxidizing of theoils. and third, drying 10 down and hardening the coating, 'thesuccessive stages being adjusted for increasing temperature anddecreasing relative humidity.

Signed at Chicago this ninetenth day of 16 January 1920.

CHARLES H. CURB-IER.

